When the previously immature and loutish Oz has developed and matured enough to be comfortable using the word "love" to describe his platonic male friendships. To Tatiana, "I don't know if you love Barry or not but I know I do."
Oz: "Auf Wiedersehen, son."
Dennis's life is still a mess, twenty years on, and he's humiliated by that fact. When the remaining friends get back together in the new series and decide to undertake the demolition project, they put Dennis in charge because "he's the gaffer - always were!"